Using a recent nearby supernova as an example, researchers have shown that cosmic rays can be produced as the supernova collides with dense circumstellar material, with a production efficiency of 10%.
If KM3-230213A arose from the interaction of an ultra-high-energy cosmic ray with the photon or matter background, the discovery is in (potentially resolvable) tension with existing cosmic-ray observations.
New information revealed about a new class of variable stars: they are evolved objects with periods of 3–75 minutes, with similar surface gravities and effective temperatures, but some differences in helium abundance.
Using N-body simulations, researchers examine the outcomes of planetesimal growth in protoplanetary disks in which planetesimals are clustered within rings rather than distributed evenly throughout the disk.
A radio megahalo surrounding a merging galaxy cluster has been observed at a frequency higher than 144 megahertz for the first time, opening up the possibility of performing spectral studies of these objects.
The discovery of an 18-solar-mass star at 34 kiloparsecs from the center of the Andromeda Galaxy, along with a wispy arm of hydrogen gas, suggest that massive stars can form in tenuous gas environments.